.TH "ATHCTRL" "8" "February 2006" "" ""
.SH "NAME"
\fBathctrl\fP \- sets the maximum distance between communicating stations
.SH "SYNOPSIS"
.B athctrl
[-h] [-i device] [-d distance]
.SH "DESCRIPTION"
\fBathctrl\fP sets the maximum distance in meters of stations with which 
communication occurs. This distance metric determines how much time the radio
waits for an acknowledgment after every transmission and it sets a few other 
derived timing parameters. This limits the distance between two stations at 
which the collision avoidance, acknowledgment, retransmission protocols will 
work correctly. 
.PP
In particular, when transmitting to too distant stations the radio will start 
retransmitting packets before an ACK can possibly have been received causing 
unnecessary retransmissions and collisions. The distance parameter needs to be 
set properly on all stations that perform long-distance communication 
irrespective of their mode of operation (master/managed/ad-hoc). For best 
operation all stations communicating with each other should be set to the same
value.
.PP
.SH "OPTIONS"
.TP
.B \-i device
The madwifi device to apply the settings to. If no device is specified,
\fBathctrl\fP defaults to wifi0.
.TP
.B \-d distance
Distance in metric meters.
.TP 
.B \-h
Display usage.
.PP
.SH "EXAMPLES"
.TP
.B athctrl \-i wifi1 \-d 500
Set maximum distance of 500m for wifi1.
.TP
.B athctrl 1000
Set maximum distance of 1000m for wifi0.
.PP
.SH "SEE ALSO"
\fBathchans\fP(8), \fBathkey\fP(8), \fBathstats\fP(8)
.SH "AUTHOR"
This manual page was written by Kel Modderman <kelrin@tpg.com.au> and was based
upon previous text written by Eric S. Raymond and Thorsten von Eicken.
